261144801 has 6 divisors (see below), whose sum is σ = 377209170. Its totient is φ = 174096528.

The previous prime is 261144787. The next prime is 261144817. The reversal of 261144801 is 108441162.

It is a happy number.

261144801 is a `hidden beast` number, since 2 + 611 + 4 + 48 + 0 + 1 = 666.

It can be written as a sum of positive squares in only one way, i.e., 242611776 + 18533025 = 15576^2 + 4305^2 .

It is not a de Polignac number, because 261144801 - 2⁷ = 261144673 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261144901) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14508036 + ... + 14508053.

It is an arithmetic number, because the mean of its divisors is an integer number (62868195).

Almost surely, 2^261144801 is an apocalyptic number.

It is an amenable number.

261144801 is a deficient number, since it is larger than the sum of its proper divisors (116064369).

261144801 is a wasteful number, since it uses less digits than its factorization.

261144801 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29016095 (or 29016092 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 27.

The square root of 261144801 is about 16159.9752784464. The cubic root of 261144801 is about 639.1858144330.

Adding to 261144801 its reverse (108441162), we get a palindrome (369585963).

The spelling of 261144801 in words is "two hundred sixty-one million, one hundred forty-four thousand, eight hundred one".